Transmission fluid leaking from the front of the transmission bell housing may also be accompanied with shifting and transmission engagement issues. This is often caused by transmission overheating and is the sign of a significant internal transmission problem. The superficial cause is the failure of the front pump seal of the transmission. The immediate repair is to remove the transmission, replace the front pump and seal, replace all fluid with the transmission filter, and verify proper flow through the transmission fluid lines and cooler. It is also recommended to make sure the vehicle is not pulling a load that is heavier than the gross vehicle weight limits because this can cause the transmission to overheat. Depending on the transmission's mileage, this can also be a good time to consider a complete overhaul or replacement with a remanufactured unit, as often just the pump and seal replacement is a short lived remedy. This concern relates specifically to the E4OD and 4R100 automatic transmissions.

This concern relates to vehicles equipped with the E4OD and 4R100 automatic transmissions. Fluid leaks from the rear of the transmission and excessive vibration felt in the vehicle while driving can be caused by a lack of lubrication to the rear of the transmission and rear seal failure. The extension housing (rear portion of transmission) can lose lubrication if the fluid supply hole becomes clogged. This leads to rear seal failure from lack of lubrication, and can cause bearing failure in the extension housing. The extension housing and gasket should be replaced and verify the fluid supply hole is clear of debris.

The front end may make a rattle noise over bumps. There may be handling issues, and play in the front wheels on inspection. If there is up and down movement on the front wheels while the lower control arms are being supported, inspect the upper and lower ball joints for excessive play. These are prone to failure from moisture entry and lack of lubrication. The ball joints should be replaced as needed.

Electrolysis can cause repeated failures of the heater core and radiator. The diagnosing technician should check for voltage present in the coolant, with the battery disconnected, because electrical current in the coolant causes electrolysis. Corroded or deteriorated parts should be replaced, and the coolant should be flushed. Ground straps can be added to help prevent future corrosion of components.

If a buzzing noise is coming from the exhaust at different engine speeds and conditions, this is commonly caused by the heat shields on catalytic converters coming loose at points. The buzzing is the metal on metal contact. Installing a large worm clamp around the catalytic converter and heat shield assembly will prevent the noise and secure the shields.